When selecting a specific date is not possible while entering data in weekly units

[pi314267]

I'm trying to improve the speed by setting the Row to 1 and PageStartMode to FirstDayOfWeek.

However, when entering information by week, if the month changes and the next month is included in the last week of the previous month, it becomes disabled and cannot be selected.

Is it possible to enable the disabled part?

[ME-MarvinE]

Yee, there are multiple ways to do this

From C#:

• Inherit from the Calendar class and override the "IsDateTimeInvalid" method to return false. (By default, the "UpdateDays" method uses this method to set the IsInvalid property of the CalendarDay).

• Inherit from the Calendar class and override the "UpdateDay" method and set the Day's IsInvalid property to false. Make sure to call the base method so it can still update the other values of the Day (such as IsCurrentMonth) and to do it at the start otherwise your values will get overwritten.

From XAML:

• Use a DayView in the CalendarView's DayTemplate property and set its IsInvalid property to false instead of binding it to the underlying CalendarDay's IsInvalid property.

[pi314267]

Hi MarvinE,
I tried working with the method you suggested, but it remains inactive.
In case you didn't understand my explanation,

I'll provide more details. As a Korean, I set the beginning of the week to "Sunday".

Now, for example, I'll try the following steps:

1. Set the Row of XCalendar.Core.Models.Calendar to "1", and PageStartMode to "FirstDayOfWeek".

2. If you look at the last week of March 2023, (Sat) is inactive. Moreover, Sat is in April.
   

3. Now, I'll try to navigate and increase it by 1 Week. Is there no way to select April 1, 2023?
   

C# Part

public class XXCalendar : Calendar<HabitDay>
    {
        public XXCalendar() { }
        public override bool IsDateTimeInvalid(DateTime dateTime)
        {
            //return base.IsDateTimeInvalid(dateTime);
            return false;
        }
        public override void UpdateDay(HabitDay day, DateTime newDateTime)
        {
            base.UpdateDay(day, newDateTime);
            day.IsInvalid = false;
        }
    }

Xaml Part

<xc:CalendarView.DayTemplate>
                    <DataTemplate x:DataType="{x:Type Models:EventDay}">
                        <Border
                            Margin="0"
                            Padding="0"
                            BackgroundColor="Transparent"
                            HeightRequest="100"
                            WidthRequest="50">

                            <Border.StrokeShape>
                                <!--<Ellipse/>-->
                                <RoundRectangle CornerRadius="10"/>
                            </Border.StrokeShape>

                            <xc:DayView
                                CurrentMonthCommand="{Binding BindingContext.ChangeDateSelectionCommand, Source={x:Reference This}}"
                                CurrentMonthCommandParameter="{Binding DateTime}"
                                DateTime="{Binding DateTime}"
                                IsCurrentMonth="{Binding IsCurrentMonth}"
                                IsInvalid="False"
                                IsSelected="{Binding IsSelected}"
                                IsToday="{Binding IsToday}"
                                SelectedCommand="{Binding BindingContext.ChangeDateSelectionCommand, Source={x:Reference This}}"
                                SelectedCommandParameter="{Binding DateTime}"
                                Style="{StaticResource DefaultDayViewStyle}"
                                TodayCommand="{Binding BindingContext.ChangeDateSelectionCommand, Source={x:Reference This}}"
                                TodayCommandParameter="{Binding DateTime}"
                                HeightRequest="100">

[ME-MarvinE]

Wow, sorry, its the IsCurrentMonth property that needs to be always set to true. I mixed the properties up.

For future reference, by default, a day will not have black text colour if IsCurrentMonth is false or IsInvalid is true.

[pi314267]

Now it works properly.
XCalendar is great due to its high flexibility.
The speed aspect is a bit concerning, but I believe it will be resolved.
For the speed issue, I suggest trying to use the Communicationtoolkit.

[ME-MarvinE]

I assume you mean the MAUI Community Toolkit, .NET Community Toolkit etc. Is there anything specifically from these that you believe may help?

[pi314267]

Yeah, you're right about the MAUI Community Toolkit.
To be honest, I don't think there will be a significant difference.
Currently, the speed issue seems to arise when rendering the screen. This problem is most closely related to the performance of the phone, and consequently, improvements in the performance of the MAUI Core need to be made first for XCalendar's performance to increase as well.

However, the reason I recommend the Communication ToolKit is that, as you may know, when you use [ObserveProperty], each variable is created globally, and I speculate that it might be slightly advantageous when binding. It seems like there might be an issue with the binding part as well.